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101.
Tatiana N. Laremore Kemal Solakyildirim Robert J. Linhardt 《Analytical biochemistry》2010,401(2):236-1370
Separation of milligram amounts of heparin oligosaccharides ranging in degree of polymerization from 4 to 32 is achieved within 6 h using continuous elution polyacrylamide gel electrophoresis (CE-PAGE) on commercially available equipment. The purity and structural integrity of CE-PAGE-separated oligosaccharides are confirmed by strong anion exchange high-pressure liquid chromatography, electrospray ionization Fourier transform mass spectrometry, and two-dimensional nuclear magnetic resonance spectroscopy. The described method is straightforward and time-efficient, affording size-homogeneous oligosaccharides that can be used in sequencing, protein binding, and other structure-function relationship studies. 相似文献
102.
Timothy L Fitzgerald Kemal Kazan Zhongyi Li Matthew K Morell John M Manners 《BMC plant biology》2010,10(1):264
Background
Mutational inactivation of plant genes is an essential tool in gene function studies. Plants with inactivated or deleted genes may also be exploited for crop improvement if such mutations/deletions produce a desirable agronomical and/or quality phenotype. However, the use of mutational gene inactivation/deletion has been impeded in polyploid plant species by genetic redundancy, as polyploids contain multiple copies of the same genes (homoeologous genes) encoded by each of the ancestral genomes. Similar to many other crop plants, bread wheat (Triticum aestivum L.) is polyploid; specifically allohexaploid possessing three progenitor genomes designated as 'A', 'B', and 'D'. Recently modified TILLING protocols have been developed specifically for mutation detection in wheat. Whilst extremely powerful in detecting single nucleotide changes and small deletions, these methods are not suitable for detecting whole gene deletions. Therefore, high-throughput methods for screening of candidate homoeologous gene deletions are needed for application to wheat populations generated by the use of certain mutagenic agents (e.g. heavy ion irradiation) that frequently generate whole-gene deletions. 相似文献103.
104.
Several species ofHypericum are used in traditional Turkish folk medicine. Their most medicinally important secondary metabolites are the hypericins,
hyperforins, and phenolics. Here, we determined the ontogenetic, morphogenetic, and diurnal variations in total phenolics
contents fromH. aviculariifolium subsp.depilatum var.depilatum (endemic),H. perforation, andH. pruinatum. Plants of wild-growingH. aviculariifolium subsp.depilatum var.depilatum andH. perforatum, and greenhouse-grownH. pruinatum were harvested four times per day during their vegetative, floral-budding, full-flowering, fresh-fruiting, and mature-fruiting
stages. They were then dissected into stem, leaf, and reproductive tissues to be dried separately and assayed. The highest
level of phenolics inH. aviculariifolium subsp.depilatum var.depilatum andH. pruinatum was found in the leaves, whereas the floral buds produced the greatest amount inH. perforatum. Variations in contents from whole plants fluctuated diurnally, differing among species over the course of ontogenesis, reaching
the highest level at floral-budding and tending to increase at mid-day inH. aviculariifolium subsp.depilatum var.depilatum. ForH. perforatum andH. pruinatum, contents also were the highest during floral development, although no diurnal fluctuations were observed in those species. 相似文献
105.
Campbell EJ Schenk PM Kazan K Penninckx IA Anderson JP Maclean DJ Cammue BP Ebert PR Manners JM 《Plant physiology》2003,133(3):1272-1284
The ATP-binding cassette (ABC) transporters are encoded by large gene families in plants. Although these proteins are potentially involved in a number of diverse plant processes, currently, very little is known about their actual functions. In this paper, through a cDNA microarray screening of anonymous cDNA clones from a subtractive library, we identified an Arabidopsis gene (AtPDR12) putatively encoding a member of the pleiotropic drug resistance (PDR) subfamily of ABC transporters. AtPDR12 displayed distinct induction profiles after inoculation of plants with compatible and incompatible fungal pathogens and treatments with salicylic acid, ethylene, or methyl jasmonate. Analysis of AtPDR12 expression in a number of Arabidopsis defense signaling mutants further revealed that salicylic acid accumulation, NPR1 function, and sensitivity to jasmonates and ethylene were all required for pathogen-responsive expression of AtPDR12. Germination assays using seeds from an AtPDR12 insertion line in the presence of sclareol resulted in lower germination rates and much stronger inhibition of root elongation in the AtPDR12 insertion line than in wild-type plants. These results suggest that AtPDR12 may be functionally related to the previously identified ABC transporters SpTUR2 and NpABC1, which transport sclareol. Our data also point to a potential role for terpenoids in the Arabidopsis defensive armory. 相似文献
106.
Demirci B Dadandi MY Paper DH Franz G Başer KH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):826-829
Phlomis linearis Boiss. & Bal. of the Lamiaceae family growing in central, east and southeast Anatolia is an endemic species for Turkey. The essential oil obtained from the aerial parts by hydro distillation was subsequently analyzed by GC/MS. The main components of the oil were found as beta-caryophyllene (24.2%), germacrene D (22.3%) and caryophyllene oxide (9.2%), among 49 identified compounds, representing 94.5% of the total essential oil. The overall biological activity of the essential oil (100 microg/pellet) was tested on the chorioallantoic membrane (CAM) of the fertilized hen's egg in order to examine the anti-angiogenic and anti-inflammatory activity. None of the tests showed pronounced activity, toxicity or irritation at the tested concentration. 相似文献
107.
Irmak MK Fadillioğlu E Güleç M Erdoğan H Yağmurca M Akyol O 《Cell biochemistry and function》2002,20(4):279-283
The number of reports on the effects induced by electromagnetic radiation (EMR) in various cellular systems is still increasing. Until now no satisfactory mechanism has been proposed to explain the biological effects of this radiation. Oxygen free radicals may play a role in mechanisms of adverse effects of EMR. This study was undertaken to investigate the influence of electromagnetic radiation of a digital GSM mobile telephone (900 MHz) on oxidant and antioxidant levels in rabbits. Adenosine deaminase, xanthine oxidase, catalase, myeloperoxidase, superoxide dismutase (SOD) and glutathione peroxidase activities as well as nitric oxide (NO) and malondialdehyde levels were measured in sera and brains of EMR-exposed and sham-exposed rabbits. Serum SOD activity increased, and serum NO levels decreased in EMR-exposed animals compared to the sham group. Other parameters were not changed in either group. This finding may indicate the possible role of increased oxidative stress in the pathophysiology of adverse effect of EMR. Decreased NO levels may also suggest a probable role of NO in the adverse effect. 相似文献
108.
109.
Aykan Karademir Seda Aslan Kilavuz Mahmut Kemal Korucu Ertan Durmusoglu 《人类与生态风险评估》2013,19(2):341-353
We present an estimation of dietary exposure to PCDD/Fs by animal products in Kocaeli, a highly polluted area in Turkey, based on current food data consumption. The calculation of the PCDD/F intakes by an exposure methodology concerning consumption habits of different receptor groups in Kocaeli was included. The data relate to the PCDD/F levels in food groups of animal origin (milk, egg, meat, chicken, and fish), food consumption rates, and the fractions of locally grown foods in total consumption were statistically assessed. Monte Carlo simulation was used to estimate the ranges of PCDD/F doses through the consumption of animal products. The PCDD/F intakes through the consumption of animal products were calculated to average between 0.4–1.8 pg WHO-TEQ.kg?1 bodyweight (bw).day?1. The results are within the range of 1–4 pg WHO-TEQ.kg?1 bw.day?1, proposed as the tolerable daily intake by the World Health Organization. On the other hand, contributions of the consumption of different foods to the total PCDD/F intake and the results of sensitivity analysis showed that the PCDD/F intake in semi-urban and rural settings was determined primarily by the consumption of milk products, while consumption of meat and fish had a greater importance in urban settings. 相似文献
110.
The tropical copepod Notodiaptomus iheringi (N. iheringi) is an ideal subject for studying zooplankton responses to cyanobacteria because it co-exists with permanent blooms across widespread regions in South America in high abundance. Single and mixed diets containing Cryptomonas and either a microcystin-producing (MC+) or microcystin-lacking (MC?) Microcystis were offered to N. iheringi at different proportions in a 10-day laboratory survival test to distinguish between the effects of toxicity versus nutrition. As expected, the pure MC+ Microcystis diet caused acute toxicity, indicated by high mortality compared to starved copepods. Both Microcystis strains were ingested in a 3-h short-term grazing experiment with pure diets. Despite its toxicity as the sole food source, survival was unaffected by MC+ Microcystis in mixed food diets. Even when MC+ Microcystis was 90% of the total food, survival was similar to the control with 10% Cryptomonas only. Hence, the survival in mixed food diets was controlled by the amount of Cryptomonas, not Microcystis. Previous reports show strong negative effects of Microcystis on copepod survival despite abundant high-quality food. Although this is the first example of copepods avoiding acute Microcystis toxicity in mixed diets, it could be a common trait where permanent blooms dominate the ecosystem. 相似文献